Imaging based feedback cooling of a levitated nanoparticle

TL;DR

This paper demonstrates a camera-based feedback cooling method for levitated nanoparticles, using real-time image processing and phase-delayed feedback to achieve velocity damping in a linear Paul trap.

Contribution

It introduces a simple, versatile imaging-based feedback cooling technique for levitated nanoparticles, complementing existing detection methods.

Findings

Successful camera-based feedback cooling of a levitated nanoparticle

Real-time image processing integrated with microcontroller for position detection

Effective velocity damping achieved through phase-delayed feedback

Abstract

Imaging-based detection of the motion of the levitated nanoparticles complements a widely-used interferometric detection method, providing a precise and robust way to estimate the position of the particle. Here, we show the camera-based feedback cooling of a charged nanoparticle levitated in a linear Paul trap. A charged nanoparticle levitated in a vacuum was observed by CMOS camera systems. The nanoparticle images were processed in realtime with a microcontroller integrated with a CMOS image sensor. The phase-delayed position signal was fed-back to one of the trap electrodes resulting in the velocity damping cooling. Our study provides a simple and versatile approach applicable for control of low-frequency mechanical oscillators.